Warp knitting machine having exhausted spool detector and spool therefor

ABSTRACT

The warp beam of a knitting machine carries a spool of yarn from which a plurality of threads extend to the knitting instrumentalities of the machine. A means, such as a strip of tape adhesively secured to the threads, extends transversely across at least two adjacent threads at a point close to the ends of the threads which are first wound on the spool. Sensing means, such as an element arranged between the two threads in the path of movement of the tape, detects the tape and in response thereto a switch is operated to terminate operation of the machine. Each spool on the warp beam is furnished with a tape, and a separate sensing means is arranged to detect the tape of each spool.

I Umted States Patent [1 1 1111 3,751,937 Bassist Aug. 14, 1973 1 WARP KNITTING MACHINE HAVING 1,372,978 3/1921 Richardson 26/17 EXHAUSTED spoo DETECTOR AND 496,532 5/1893 Pearson et a1. 26/17 3,534,188 10/1970 Holm et a1 26/17 SPOOL THEREFOR 2,430,538 11/1947 Somers 242/188 [76] Inventor: Rudolph G. Bassist, 2,900,142 8/1959 Sprinkle 242/188 Lancaster, Pa. [73] Assignee: Travis Mills Corp., New York, Primary Examiner-Ronald Feldbaum N.Y.. a part interest Attorney-Alan 1-1. Levine [22] Filed: Dec. 13, 1971 [57] ABSTRACT [21 1 Appl 207494 The warp beam of a knitting machine carries a spool of yarn from which a plurality of threads extend to the 52 0.8. (:1 66/86 A, 28/50, 28/51, knitting instrumentalities of the machine A means, 66/163, 66/161, 139/353 such as a strip of tape adhesively secured to the 51 1111.01. D04b 23/00, D04b 27/00 threads, extends transversely across at least two j [58] Field of Search 28/50, 51, 33; cent threads at a point close to the ends of the threads 66/163, 161; 2112/1251, 138 which are first wound on the spool. Sensing means, such as an element arranged between the two threads [56] Refere ce Cit d in the path of movement of the tape, detects the tape UNITED STATES PATENTS and in response thereto a switch is operated to terminate operation of the machine. Each spool on the warp 3: 22: beam is furnished with a tape, and a separate sensing 3:161:941 12/1964 161111 22:11:... 1:11:11: 28/72I5 means is "ranged detect the tape of each 2,738,176 3/1956 Hargenrater 28/22 2,537,007 1/1951 Abbott 28/72.5 9 Cflalms, 2 Drawmg Figures 2,214,384 9/1940 Roby et a1. 242/10 3,059,309 10/1962 Blanton 28/51 X WARP KNITTING MACHINE HAVING EXHAUSTED SPOOL DETECTOR AND SPOOL THEREFOR This invention relates to warp knitting machines, and more particularly to the spools of yarn used with such machines.

Warp knitting machines may have one or more warp beams, each beam usually carrying several spools of yarn. A plurality of threads are spirally wound in sideby-side fashion on each spool, and these threads extend to the knitting instrumentalities of the machine, During the knitting operation, the threads are of course withdrawn, i.e., unwound, from the spools.

At the present time, there is no way of knowing precisely when the yarn on any particular spool will be used up. The machine operator must be alert and try to stop the machine before any one of the spools is spent so that the spools can be replaced with full ones. However, since each spool contains many thousands of yards of yarn, it is possible for one spool on the warp beam to have several yards less than the other spools. As a result, it is not unusual for one spool to run out before the machine operator contemplates, whereupon the ends of all the threads on that spool fall into the knitting instrumentalities. When this happens, the knitting needles and threads guides, which normally intermesh, are thrown out of their proper alignment and become ruined. Consequently, the entire needle bar, and sometimes the guide bar, must be removed and replaced. This not only involves the expense of a new needle bar and the time of a repair person, but in addition the machine is put out of operation while the repair is being made.

It is an object of the present invention to avoid possible damage to the knitting instrumentalities of a knitting machine by terminating operation of the machine just before any spool of yarn on the warp beam is completely exhausted.

It is another object of the invention to provide each spool with an indicator near the ends of its yarn which are f rst wound on the spool, and to provide the machine with a detector for sensing each such indicator and shutting off the machine when any indicator is sensed.

Additional objects and features of the invention will be apparent from. the following description in which reference is made to the accompanying drawings.

In the drawings:

FIG. 1 is a perspective view of parts of a warp knitting machine according to the invention; and

FIG. 2 is a view similar to FIG. I. when the spools of yarn are nearly empty.

The machine chosen to illustrate the present invention includes a warp beam 10, mounted in the stationary machine frame, only a portion of which is shown at l l. Warp beam carries a plurality of rotatable spools of yarn l2, l3, and 14. A plurality of threads are spirally wound in side-by-side fashion on each spool, and these threads extend from the spools to the knitting instrumentalities of the machine. These instrumentalities are represented by the needle 16 and thread guide 17 shown in FIG. 1, but it isto be understood that as is usual in these machines there are many needles I6 and a thread-guide 17 for each thread 15.

According to the present invention, each of the spools 12 -14. is furnished with means extending transversely across at least two adjacent threads 15 at a point close to the ends of the threads which are first wound on the spool. In the present example, this transverse means is a strip of tape 20 adhesively secured to the threads and extending across substantially all the threads wound onthe spool. It is contemplated that the tape may be of the type having a pressure-sensitive adhesive on one face, and that when the threads 15 are initially being wound on each spool, winding will be stopped after about five yards of each thread has been wound, the tape 20 pressed on to the threads, and winding then continued until completed.

The present invention also provides a means for sensing the tape 20 of any spool 12-14 and terminating operation of the knitting machine in response thereto. In this example, the sensing means includes a rod 21 extending crosswise of threads 15 and being rotatably supported at its ends in the machine frame 11. Fixed to rod 21 are a number of thin but rigid plates 22, there being one plate for each spool. Each plate 22 is arranged in a plane perpendicular to the plane containing all the threads 15 extending from its respective spool, and is located at a point between the spool and the knitting instrumentalities. Each'plate 22 is arranged between two adjacent threads 15 extending from its respective spool, so that it is in the path of movement of tape 20 when the latter leaves the spool. Where, as in the present example, tape 20 extends across substantially all the threads 15 on a spool, plate 22 may be lo cated between any two adjacent threads.

Also fixed, to rod 21 is an actuator 23 cooperable with an electric switch 24 fixed to the machine frame. Switch 24 is arranged in a circuit relationship with the drive motor of the machine, and normally the circuit is closed through the switch. However, when the push button 25 of the switch is depressed by actuator 23, as indicated in FIG. 2, the switch is opened and operation of the machine is terminated.

From the above description it will be appreciated that when any of the spools, such as the spool 12 in FIG. 2, is nearly exhausted, the thread portion to which tape 20 is secured will be unwound and move toward the knitting instrumentalities. As the tape passes the plate 22 associated with that particular spool, the tape strikes the plate and pivots rod 21 from the position shown in FIG. 1 to that shown in FIG. 2. As a result, actuator 23 swings into engagement with push button 25 of switch 24 and terminates operation of the machine. Thus, the machine is stopped before any spool is completely exhausted and hence before the ends of any threads fall into the knitting instrumentalities.

The embodiment of the invention described above is preferred because it is particularly simple and inexpensive. However, other ways of carrying the invention into practice readily come to mind. For example, a separate switch might be mounted adjacent to the threads extending from each spool, and a switch actuator project between two adjacent threads. Also, tape 20 need not necessarily be. physically sensed as described above; the tape or a suitable substitute might for example be sensed by a photoelectric cell once all the yarn wound upon it has been withdrawn from the spool.

The invention has been shown and described in preferred form only, and by way of example, and many variations may be made in the invention which will still be comprised within its spirit. It is understood, therefore, that the invention is not limited to any specific form or embodiment except insofar as such limitations are included in the appended claims.

What is claimed is:

l. A warp knitting machine having a warp beam, knitting instrumentalities, and at least one spool of yarn mounted on said warp beam and from which a plurality of individual threads extend to said instrumentalities, characterized by means extending transversely across at least two adjacent threads wound on said spool at a point close to the ends of said threads which are first wound on said spool, means for sensing said transverse means after all the yarn wound upon it has been withdrawn from said spool, indicating that the spool of yarn is about to be exhausted, and means responsive to sensing of said transverse means by said sensing means for terminating the operation of said knitting machine.

2. A warp knitting machine as defined in claim 1 wherein said transverse means is means interconnecting at least two adjacent threads.

3. A warp knitting machine as defined in claim 1 wherein said transverse means is a strip adhesively secured to said threads.

4. A warp knitting machine as defined in claim 1 wherein said transverse means extends across substantially all the threads wound on said spool.

5. A warp knitting machine as defined in claim 1 wherein said sensing means senses the movement of said transverse means from said spool toward said instrumentalities.

6. A warp knitting machine as defined in claim 1 wherein said sensing means is an element arranged between said two adjacent threads at a point between said spool and said instrumentalities.

7. A warp knitting machine as defined in claim 1 wherein-wherein said knitting machine has a plurality of spools of yarn mounted on said warp beam, a plurality of indivisual threads extending from each spool to said instrumentalities, and including means on each spool extending transversely across at least two adjacent threads wound on that spool at a point close to the ends of said threads which are first wound on the spool, means for sensing said transverse means of each spool after the yarn wound upon it has been withdrawn from the spool, and means responsive to sensing said transverse means of any one of said spools by said sensing means for terminating the operation of said knitting machine.

8. A warp knitting machine as defined in claim 7 wherein said sensing means includes a pivotally mounted rod arranged cross-wise of said threads, an element extending from said rod into the path of movement of the transverse means of each spool, so that when any of said transverse means strikes its respective element said element and said rod are pivoted, and said responsive means includes an electric switch, and an actuator mounted on said rod and pivotable into engagement with said switch when said rod is pivoted by contact of one of said elements by its respective transverse means.

9. A warp knitting machine as defined in claim 1 wherein said transverse means is spaced along the length of said threads from the ends of said threads which are first wound on said spool, the length of the thread portions between said transverse means and said ends comprising a number of turns of thread on said spool, whereby when said sensing means senses said transverse means the end portions of said threads are still wound on said spool. 

1. A warp knitting machine having a warp beam, knitting instrumentalities, and at least one spool of yarn mounted on said warp beam and from which a plurality of individual threads extend to said instrumentalities, characterized by means extending transversely across at least two adjacent threads wound on said spool at a point close to the ends of said threads which are first wound on said spool, means for sensing said transverse means after all the yarn wound upon it has been withdrawn from said spool, indicating that the spool of yarn is about to be exhausted, and means responsive to sensing of said transverse means by said sensing means for terminating the operation of said knitting machine.
 2. A warp knitting machine as defined in claim 1 wherein said transverse means is means interconnecting at least two adjacent threads.
 3. A warp knitting machine as defined in claim 1 wherein said transverse means is a strip adhesively secured to said threads.
 4. A warp knitting machine as defined in claim 1 wherein said transverse means extends across substantially all the threads wound on said spool.
 5. A warp knitting machine as defined in claim 1 wherein said sensing means senses the movement of said transverse means from said spool toward said instrumentalities.
 6. A warp knitting machine as defined in claim 1 wherein said sensing means is an element arranged between said two adjacent threads at a point between said spool and said instrumentalities.
 7. A warp knitting machine as defined in claim 1 wherein wherein said knitting machine has a plurality of spools of yarn mounted on said warp beam, a plurality of indivisual threads extending from each spool to said instrumentalities, and including means on each spool extending transversely across at least two adjacent threads wound on that spool at a point close to the ends of said threads which are first wound on the spool, means for sensing said transverse means of each spool after the yarn wound upon it has been withdrawn from the spool, and means responsive to sensing said transverse means of any one of said spools by said sensing means for terminating the operation of said knitting machine.
 8. A warp knitting machine as defined in claim 7 wherein said sensing means includes a pivotally mounted rod arranged cross-wise of said threads, an element extending from said rod into the path of movement of the transverse means of each spool, so that when any of said transverse means strikes its respective element said element and said rod are pivoted, and said responsive means includes an electric switch, and an actuator mounted on said rod and pivotable into engagement with said switch when said rod is pivoted by contact of one of said elements by its respective transverse means.
 9. A warp knitting machine as defined in claim 1 wherein said transverse means is spaced along the length of said threads from the ends of said threads which are first wound on said spool, the length of the thread portions between said transverse means and said ends comprising a number of turns of thread on said spool, whereby when said sensing means senses said transverse means the end portions of said threads are still wound on said spool. 